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improve pre-processing

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This commit is contained in:
Nikolaj Bjorner 2022-04-15 12:55:17 +02:00
parent a634876180
commit 3cc9d7f443
22 changed files with 147 additions and 80 deletions
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122
src/util/max_cliques.h
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@ -20,6 +20,7 @@ Notes:
#include "util/vector.h"
#include "util/uint_set.h"
#include "util/heap.h"
template<class T>
@ -43,12 +44,9 @@ class max_cliques : public T {
m_seen1.insert(p);
if (m_seen2.contains(p)) {
unsigned_vector const& tc = m_tc[p];
for (unsigned j = 0; j < tc.size(); ++j) {
unsigned np = tc[j];
if (goal.contains(np)) {
for (unsigned np : tc)
if (goal.contains(np))
reachable.insert(np);
}
}
}
else {
unsigned np = negate(p);
@ -61,29 +59,30 @@ class max_cliques : public T {
for (unsigned i = m_todo.size(); i > 0; ) {
--i;
p = m_todo[i];
if (m_seen2.contains(p)) {
if (m_seen2.contains(p))
continue;
}
m_seen2.insert(p);
unsigned np = negate(p);
unsigned_vector& tc = m_tc[p];
if (goal.contains(np)) {
if (goal.contains(np))
tc.push_back(np);
}
else {
unsigned_vector const& succ = next(np);
for (unsigned j = 0; j < succ.size(); ++j) {
tc.append(m_tc[succ[j]]);
}
}
else
for (unsigned s : next(np))
tc.append(m_tc[s]);
}
}
unsigned_vector const& next(unsigned vertex) const { return m_next[vertex]; }
void init(unsigned_vector const& ps) {
unsigned max = 0;
for (unsigned p : ps) {
unsigned np = negate(p);
max = std::max(max, std::max(np, p) + 1);
}
m_next.reserve(max);
m_tc.reserve(m_next.size());
}
public:
void add_edge(unsigned src, unsigned dst) {
@ -94,20 +93,11 @@ public:
}
void cliques(unsigned_vector const& ps, vector<unsigned_vector>& cliques) {
unsigned max = 0;
unsigned num_ps = ps.size();
for (unsigned i = 0; i < num_ps; ++i) {
unsigned p = ps[i];
unsigned np = negate(p);
max = std::max(max, std::max(np, p) + 1);
}
m_next.reserve(max);
m_tc.reserve(m_next.size());
init(ps);
unsigned_vector clique;
uint_set vars;
for (unsigned i = 0; i < num_ps; ++i) {
vars.insert(ps[i]);
}
for (unsigned v : ps)
vars.insert(v);
while (!vars.empty()) {
clique.reset();
@ -118,9 +108,8 @@ public:
m_reachable[turn].remove(p);
vars.remove(p);
clique.push_back(p);
if (m_reachable[turn].empty()) {
if (m_reachable[turn].empty())
break;
}
m_reachable[!turn].reset();
get_reachable(p, m_reachable[turn], m_reachable[!turn]);
turn = !turn;
@ -129,10 +118,75 @@ public:
if (clique.size() == 2 && clique[0] == negate(clique[1])) {
// no op
}
else {
else
cliques.push_back(clique);
}
}
}
// better quality cliques
void cliques2(unsigned_vector const& ps, vector<unsigned_vector>& cliques) {
uint_set all_vars, todo;
u_map<uint_set> conns;
init(ps);
struct compare_degree {
u_map<uint_set>& conns;
compare_degree(u_map<uint_set>& conns): conns(conns) {}
bool operator()(unsigned x, unsigned y) const {
return conns[x].num_elems() < conns[y].num_elems();
}
};
compare_degree lt(conns);
heap<compare_degree> heap(m_next.size(), lt);
for (unsigned p : ps) {
all_vars.insert(p);
todo.insert(p);
}
for (unsigned v : ps) {
uint_set reach;
get_reachable(v, all_vars, reach);
conns.insert(v, reach);
heap.insert(v);
}
while (!todo.empty()) {
unsigned v = heap.min_value();
uint_set am1;
unsigned_vector next;
for (unsigned n : conns[v])
if (todo.contains(n))
next.push_back(n);
std::sort(next.begin(), next.end(), [&](unsigned a, unsigned b) { return conns[a].num_elems() < conns[b].num_elems(); });
for (unsigned x : next) {
if (std::all_of(am1.begin(), am1.end(), [&](unsigned y) { return conns[x].contains(y); }))
am1.insert(x);
}
am1.insert(v);
for (unsigned x : am1) {
todo.remove(x);
for (unsigned y : conns[x]) {
conns[y].remove(x);
heap.decreased(y);
}
}
for (unsigned x : am1)
heap.erase(x);
if (am1.num_elems() > 1) {
unsigned_vector mux;
for (unsigned x : am1)
mux.push_back(x);
if (mux.size() == 2 && mux[0] == negate(mux[1])) {
continue;
}
cliques.push_back(mux);
}
}
}